Organic Matter in Raw Water

Organic matter in raw water can be classified into two categories: naturally occurring and pollutants. Naturally organic matter will be present in raw water from a surface water or groundwater source influenced by surface water, which is extremely low and which is dependent on the source of the ground water.

Natural organic matter in raw water can be classified into a light molecular weight and a heavy molecular weight. Light molecular weight component like fulvic acid and heavy molecular weight component like humic acid.

Concentration of these matters are very important to design water treatment techniques. The fulvic acid are simple organic matters which is easily removed. But the other hand, humic acids exhibits complex properties with a large range of molecular weight molecules and varying chemical structure.

It is impossible to define the nature of the molecule accurately, since humic acid has no single chemical structure but rather an infinite number of molecular structures. Humic acid concentration is extremely important in water treatment systems. i.e., its concentration and characteristics determines the life of activated carbon media, fouling of anion exchange resins; fouling of UF and RO membranes.

Pharmaceutical water purification systems consist of RO technology. Due to presence of organic matter fouling of membranes can occur, microbial fouling attributed to the uncontrolled multiplication of bacteria on membrane surfaces from nutrients provided by organic matter.

Pollutants is a second increasingly important source of organic matter present in a raw water (e.g., industrial waste, fertilizers, and pesticides). The U.S. EPA has defined a significant number of organic compounds that are considered pollutants, with maximum concentrations for each (U.S. EPA, 2009).